From patchwork Sun Oct 7 09:38:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Jernej_=C5=A0krabec?= X-Patchwork-Id: 10630167 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A6EB415E9 for ; Mon, 8 Oct 2018 07:44:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 98A1E281C3 for ; Mon, 8 Oct 2018 07:44:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8CF63285E2; Mon, 8 Oct 2018 07:44:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3AA4C281C3 for ; Mon, 8 Oct 2018 07:44:41 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3A3606E0EF; Mon, 8 Oct 2018 07:42:32 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.siol.net (mailoutvs43.siol.net [185.57.226.234]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8DFF989CE0 for ; Sun, 7 Oct 2018 09:39:23 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mail.siol.net (Postfix) with ESMTP id C85B9520BC5; Sun, 7 Oct 2018 11:39:20 +0200 (CEST) X-Virus-Scanned: amavisd-new at psrvmta10.zcs-production.pri Received: from mail.siol.net ([127.0.0.1]) by localhost (psrvmta10.zcs-production.pri [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id dQnvNgxfUEiy; Sun, 7 Oct 2018 11:39:20 +0200 (CEST) Received: from mail.siol.net (localhost [127.0.0.1]) by mail.siol.net (Postfix) with ESMTPS id 70ECC520BC6; Sun, 7 Oct 2018 11:39:20 +0200 (CEST) Received: from localhost.localdomain (cpe1-8-82.cable.triera.net [213.161.8.82]) (Authenticated sender: 031275009) by mail.siol.net (Postfix) with ESMTPSA id D9EF6520BC5; Sun, 7 Oct 2018 11:39:17 +0200 (CEST) From: Jernej Skrabec To: maxime.ripard@bootlin.com, wens@csie.org Subject: [PATCH v2 02/29] clk: sunxi-ng: Adjust MP clock parent rate when allowed Date: Sun, 7 Oct 2018 11:38:38 +0200 Message-Id: <20181007093905.11253-3-jernej.skrabec@siol.net> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181007093905.11253-1-jernej.skrabec@siol.net> References: <20181007093905.11253-1-jernej.skrabec@siol.net> MIME-Version: 1.0 X-Mailman-Approved-At: Mon, 08 Oct 2018 07:41:57 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, sboyd@kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, airlied@linux.ie, linux-sunxi@googlegroups.com, robh+dt@kernel.org, Laurent.pinchart@ideasonboard.com, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Currently MP clocks don't consider adjusting parent rate even if they are allowed to do so. Such behaviour considerably lowers amount of possible rates, which is very inconvenient when such clock is used for pixel clock, for example. In order to improve the situation, adjusting parent rate is considered when allowed. This code is inspired by clk_divider_bestdiv() function, which does basically the same thing for different clock type. Signed-off-by: Jernej Skrabec --- drivers/clk/sunxi-ng/ccu_mp.c | 64 +++++++++++++++++++++++++++++++++-- 1 file changed, 62 insertions(+), 2 deletions(-) diff --git a/drivers/clk/sunxi-ng/ccu_mp.c b/drivers/clk/sunxi-ng/ccu_mp.c index 5d0af4051737..0357349eb767 100644 --- a/drivers/clk/sunxi-ng/ccu_mp.c +++ b/drivers/clk/sunxi-ng/ccu_mp.c @@ -40,6 +40,61 @@ static void ccu_mp_find_best(unsigned long parent, unsigned long rate, *p = best_p; } +static unsigned long ccu_mp_find_best_with_parent_adj(struct clk_hw *hw, + unsigned long *parent, + unsigned long rate, + unsigned int max_m, + unsigned int max_p) +{ + unsigned long parent_rate_saved; + unsigned long parent_rate, now; + unsigned long best_rate = 0; + unsigned int _m, _p, div; + unsigned long maxdiv; + + parent_rate_saved = *parent; + + /* + * The maximum divider we can use without overflowing + * unsigned long in rate * m * p below + */ + maxdiv = max_m * max_p; + maxdiv = min(ULONG_MAX / rate, maxdiv); + + for (_p = 1; _p <= max_p; _p <<= 1) { + for (_m = 1; _m <= max_m; _m++) { + div = _m * _p; + + if (div > maxdiv) + break; + + if (rate * div == parent_rate_saved) { + /* + * It's the most ideal case if the requested + * rate can be divided from parent clock without + * needing to change parent rate, so return the + * divider immediately. + */ + *parent = parent_rate_saved; + return rate; + } + + parent_rate = clk_hw_round_rate(hw, rate * div); + now = parent_rate / div; + + if (now <= rate && now > best_rate) { + best_rate = now; + *parent = parent_rate; + + if (now == rate) + return rate; + } + } + } + + return best_rate; +} + static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux, struct clk_hw *hw, unsigned long *parent_rate, @@ -56,8 +111,13 @@ static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux, max_m = cmp->m.max ?: 1 << cmp->m.width; max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1); - ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p); - rate = *parent_rate / p / m; + if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) { + ccu_mp_find_best(*parent_rate, rate, max_m, max_p, &m, &p); + rate = *parent_rate / p / m; + } else { + rate = ccu_mp_find_best_with_parent_adj(hw, parent_rate, rate, + max_m, max_p); + } if (cmp->common.features & CCU_FEATURE_FIXED_POSTDIV) rate /= cmp->fixed_post_div;